listamsb: finish() cleanup, fix errmsg for -D with stdout, rm output file if empty due to error.

1 files changed, 23 insertions, 8 deletions

diff --git a/listamsb.c b/listamsb.c
index 9bf404c..ec1b027 100644
--- a/listamsb.c
+++ b/listamsb.c
@@ -5,6 +5,7 @@
 #include <string.h>
 #include <stdarg.h>
 #include <ctype.h>
+#include <sys/stat.h>
 
 #include "amsbtok.h"
 
@@ -151,6 +152,12 @@ int is_comment_start(unsigned char tok) {
 	return (tok == TOK_REM || tok == TOK_SQUOTE || tok == TOK_BANG);
 }
 
+off_t get_file_len(const char *name) {
+	struct stat st;
+	if(stat(name, &st) != 0) return 0;
+	return st.st_size;
+}
+
 /* post-processing: print "summary", exit. called by either die()
 	or main() (on normal exit). */
 void finish(int rv) {
@@ -159,9 +166,8 @@ void finish(int rv) {
 	verbose(1, "read %d bytes", bytes_read);
 	verbose(1, "listed %d line%s", linecount, plural(linecount));
 
-	if(!linecount) warn("no lines of code in program");
-
 	if(header_read) {
+		if(!linecount) warn("no lines of code in program");
 		progsize = bytes_read - 3;
 		if(proglen == progsize) {
 			verbose(1, "file size matches proglen");
@@ -175,12 +181,12 @@ void finish(int rv) {
 				fputs("AMSB will stop LOADing before the end of this file\n", stderr);
 			}
 		}
+		if(fgetc(infile) != EOF) warn("trailing garbage at end of file");
 	} else {
-		warn("file is %d byte%s, too short to be an AMSB program", bytes_read, plural(bytes_read));
+		if(feof(infile))
+			warn("file is %d byte%s, too short to be an AMSB program", bytes_read, plural(bytes_read));
 	}
 
-	if(fgetc(infile) != EOF) warn("trailing garbage at end of file");
-
 	if(warnings) {
 		fprintf(stderr, "%s: file has %d warning%s\n",
 			self, warnings, plural(warnings));
@@ -193,6 +199,11 @@ void finish(int rv) {
 		if(got != 0) {
 			os_err("a8cat child process failed, do you have a8cat on your PATH?");
 		}
+	} else {
+		fclose(outfile);
+		/* if we were writing to actual file and no data was written, rm it */
+		if(outname && get_file_len(outname) == 0)
+			unlink(outname);
 	}
 
 	verbose(2, "spaces outside strings/comments: %d (%.1f%%)",
@@ -255,7 +266,10 @@ void read_header(void) {
 	locked = read_byte();
 	if(locked > 1) die("not an AMSB file: first byte is $%02x, not $00 or $01", locked);
 
-	if(locked) verbose(1, "program is locked, decrypting");
+	if(locked)
+		verbose(1, "program is locked, decrypting");
+	else
+		verbose(1, "program is not locked");
 
 	proglen = read_word();
 
@@ -910,8 +924,9 @@ void parse_args(int argc, char **argv) {
 		if(!freopen(outname, "wb", stdout))
 			os_err("%s: %s", outname, strerror(errno));
 		verbose(1, "redirected stdout to %s", outname);
-	} else if(crunch) {
-		os_err("can't use stdout with -C, must give an output filename");
+	} else if(crunch || decrunch) {
+		os_err("can't use stdout with -%c, must give an output filename",
+			crunch ? 'C' : 'D');
 	}
 }